Term
Overwatch
Covering a position or route from range.
Overwatch is holding an angle that covers your team's position or route, ready to fire the moment a threat appears. It is the natural job of the Recon career with a Sniper Rifle or Marksman Rifle on the high ground above the Control Zone. Good overwatch turns a push into a safe one.
Know the wiki. Now play the game.
AE Gaming runs organised WARDOGS every night with free comms, a planning map and a base builder. Reading is half of it, the other half is a squad.